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Cooling To Absolute Zero Mathematically Outlawed After a Century (newscientist.com)
After more than 100 years of debate -- which at one point even elicited interest from Albert Einstein and Max Planck, physicists have finally offered up mathematical proof of the third law of thermodynamics, which states that a temperature of absolute zero cannot be physically achieved because it's impossible for the entropy (or disorder) of a system to hit zero. While scientists have long suspected that there's an intrinsic 'speed limit' on the act of cooling in our Universe that prevents us from ever achieving absolute zero (0 Kelvin, -273.15 C, or -459.67 F), this is the strongest evidence yet that our current laws of physics hold true when it comes to the lowest possible temperature. From a report on NewScientist: Now Jonathan Oppenheim and Lluis Masanes at University College London have mathematically derived the unattainability principle and placed limits on how fast a system can cool, creating a general proof of the third law. "In computer science, people ask this question all the time: how long does it take to perform a computation?" says Oppenheim. "Just as a computing machine performs a computation, a cooling machine cools a system." So, he and Masanes asked how long it takes to get cold. Cooling can be thought of as a series of steps: heat is removed from the system and dumped into the surrounding environment again and again, and each time the system gets colder. How cold depends on how much work can be done to remove the heat and the size of the reservoir for dumping it. By applying mathematical techniques from quantum information theory, they proved that no real system will ever reach 0 kelvin: it would take an infinite number of steps. Getting close to absolute zero is possible, though, and Masanes and Oppenheim quantified the steps of cooling, setting speed limits for how cold a given system can get in finite time.
Thats really cool!
Isn't this just Zeno's paradox applied to really good fridges?
I had a dream, bright and carefree, but now there's doubt and gravity
All they need to do is to heat it to below absolute zero and then let it warm up a little.
The real "Libtards" are the Libertarians!
our new president was elected to repeal. We're going to make America Cool again!
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"In this house we obey the laws of thermodynamics!"
Would this also be a property of time? That you can't reach absolute zero because doing so, would be akin to stopping time, if only for that specific single point in space?
Now that has me wondering about the singularity in a black hole. And now my brain hearts a little as so many things seem to conflict with all of this.
in the winter, pretty sure it's colder than that.
Blah blah blah...you can't go faster than light.
Blah blah blah...you can't cool to absolute zero.
I'll bet a politician would tell me I could do either one of those if it would my vote. Why can't physicists respect my desires like the nice men in suits do?
Is it just my observation, or are there way too many stupid people in the world?
Reminds me of this engineering joke:
A mathematician, a physicist, and an engineer were asked to review this mathematical problem. In a high school gym, all the girls in the class were lined up against one wall, and all the boys against the opposite wall. Then, every ten seconds, they walked toward each other until they were half the previous distance apart. The mathematician, physicist, and engineer were asked, “When will the girls and boys meet?”
The mathematician said, “Never.”
The physicist said, “In an infinite amount of time.”
The engineer said, “Well... in about two minutes, they'll be close enough for all practical purposes.”
One: I think you mean "ruled out" rather than "outlawed." That implies some sort of change in the legality rather than a revealing of a "legality" (which is a somewhat obtuse way of looking at this since science is a system of attempting to describe reality rather than an attempt to describe some sort of human invention or behavior) that already existed.
Two: This has an interesting implication for our universe, I think. It's possible that the entropy eventually reaches 0 in the universe as a whole (since this apparently applies to localized entropy), but if that's actually impossible, it means there will always be *some* sort of entropy in the universe regardless of its size. I would think this to mean that a universe "death" of expansion is preferable to a universe death of collapse, at least from the perspective of life. With no entropy, there isn't really existence.
Heat death is when there is no temperature differential and no way to make a temperature differential, not that there is a zero temperature.
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